Goop, which Gwyneth Paltrow founded as a newsletter in 2008, is no stranger to promoting questionable health products. (Paul J. Richards/AFP/Getty Images)

Gwyneth Paltrow’s lifestyle website Goop — which has been routinely criticized for promoting potentially harmful alternative health products — kicked off the new year by recommending a product used to inject coffee where the sun doesn’t shine.

As part of an overarching feature called the “Detox Guides,” the website touted the $135 Implant-O-Rama, a device used to give oneself a coffee enema at home, as a means to “Supercharge Your Detox.”

But the concept of detoxing — the idea of flushing toxins out of one’s body through a special diet or procedure — has been widely dismissed as pseudoscience.

“There isn’t any convincing evidence that detox or cleansing programs actually remove toxins from your body or improve your health,” the National Institutes of Health said on its website. It added that colon cleansing procedures or enemas, a common method of detoxing, “may have side effects, some of which can be serious.”

An enema is a medical procedure in which a liquid or gas is injected into the colon through the rectum, usually with the intent of stimulating a bowel movement. In recent years, the alternative medicine community has embraced do-it-yourself enemas — including those using coffee as the stimulant.

Goop recommended the Implant-O-Rama “for those who know what they’re doing.” The product’s main website claimed that coffee enemas “can mean relief from depression, confusion, general nervous tension, many allergy related symptoms, and, most importantly, relief from severe pain.” But Implant-O-Rama, on its site, also readily admitted this is “not necessarily based on scientific evidence from any source.”

Goop also tries to protect itself by declaring below an accompanying article that the views are not necessarily those of Goop and that the “article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment, and should never be relied upon for specific medical advice.”

Backlash against the suggestion — and the detox guide as a whole — was swift.

Harvard Medical School called detoxing a “dubious practice” on its website in 2008. “Like fasting,” it said, “colonic cleansing carries a risk of dehydration, electrolyte imbalance, impaired bowel function, and disruption of intestinal flora.”

Edzard Ernst, professor of complementary medicine at Exeter University, called the concept of detoxing both a “scandal” and “criminal exploitation of the gullible man” in a 2014 interview with the Guardian. Ernst said the body naturally removes toxins. “There is no known way — certainly not through detox treatments — to make something that works perfectly well in a healthy body work better,” he said.

In particular, enemas as a means of detoxification have been discouraged for nearly a century.

The practice of flushing out one’s colon has been around since at least the 1800s. The basic idea is that fecal matter builds up in the colon and leads to autointoxication, which is “an ancient theory based on the belief that intestinal waste products can poison the body and are a major contributor to many, if not all, diseases,” according to a report in the Journal of Clinical Gastroenterology. Colon cleanses, in theory, wash out that harmful fecal matter.

In recent years, colon cleansing, which the Journal of Clinical Gastroenterology called “not merely useless but potentially dangerous,” has experienced a resurgence. ” . . . Ignorance is celebrating a triumph over science,” the journal stated.

The National Cancer Institute warns that “too many enemas of any kind can cause changes in normal blood chemistry, chemicals that occur naturally in the body and keep the muscles, heart, and other organs working properly.”

Some experts specifically warn against using coffee as the stimulant in an enema, pointing to a lack of research on its potential effects.

“Reports of three deaths that may be related to coffee enemas have been published,” the National Cancer Institute stated, though it did not say the coffee itself was responsible. The procedure also possibly caused a rectal burn in a 47-year-old woman, according to a 2014 report in the journal Endoscopy. In another case, detailed in the American Journal of Gastroenterology, a 60-year-old woman underwent a coffee enema and later suffered severe inflammation of the colon. It’s unclear if coffee caused the inflammation, but the report stated, “Coffee enema has no proven benefit and carries considerable risk of provoking unwanted complications.”

“Colon cleansing can sometimes be harmful,” the Mayo Clinic says on its website. “In fact, coffee enemas sometimes used in colon cleansing have been linked to several deaths.”

Goop, which Paltrow founded as a newsletter in 2008, is no stranger to promoting questionable health products. The consumer advocacy group Truth in Advertising catalogued more than 50 instances in which the website made “claims, either expressly or implicitly, that its products . . . can treat, cure, prevent, alleviate the symptoms of, or reduce the risk of developing a number of ailments, ranging from depression, anxiety, and insomnia, to infertility, uterine prolapse, and arthritis, just to name a few.”

Among these products were the $66 jade eggs that are meant to be inserted into the vagina to “help cultivate sexual energy” and “increase orgasm” and the line of $38 “healing dusts,” which purport to do everything from increasing sexual pleasure to raising one’s intellect.

Though the company has been slammed again and again for its health claims, it appears to be thriving. Its revenue tripled from 2015 to 2016, according to the New York Times, and it recently teamed up with Condé Nast to create a print magazine.